Remote sensing or hyper-spectral imaging often uses the sun for illumination, and the short-wave infrared (SWIR) windows of about 1.5-1.8 microns and about 2-2.5 microns may be attractive because the atmosphere transmits in these wavelength ranges. Although the sun can be a bright and stable light source, its illumination may be affected by the time-of-day variations in the sun angle as well as weather conditions. For example, the sun may be advantageously used for applications such as hyper-spectral imaging only between about 9 am to 3 pm, and it may be difficult to use the sun during cloudy days or during inclement weather. In one embodiment, the hyper-spectral sensors measure the reflected solar signal at hundreds (e.g., 100 to 200+) contiguous and narrow wavelength bands (e.g., bandwidth between 5 nm and 10 nm). Hyper-spectral images may provide spectral information to identify and distinguish between spectrally similar materials, providing the ability to make proper distinctions among materials with only subtle signature differences. In the SWIR wavelength range, numerous gases, liquids and solids have unique chemical signatures, particularly materials comprising hydro-carbon bonds, O—H bonds, N—H bonds, etc. Therefore, spectroscopy in the SWIR may be attractive for stand-off or remote sensing of materials based on their chemical signature, which may complement other imaging information.
A SWIR super-continuum (SC) source may be able to replace at least in part the sun as an illumination source for active remote sensing, spectroscopy, or hyper-spectral imaging. In one embodiment, reflected light spectroscopy may be implemented using the SWIR light source, where the spectral reflectance can be the ratio of reflected energy to incident energy as a function of wavelength. Reflectance varies with wavelength for most materials because energy at certain wavelengths may be scattered or absorbed to different degrees. Using a SWIR light source may permit 24/7 detection of solids, liquids, or gases based on their chemical signatures. As an example, natural gas leak detection and exploration may require the detection of methane and ethane, whose primary constituents include hydro-carbons. In the SWIR, for instance, methane and ethane exhibit various overtone and combination bands for vibrational and rotational resonances of hydro-carbons. In one embodiment, diffuse reflection spectroscopy or absorption spectroscopy may be used to detect the presence of natural gas. The detection system may include a gas filter correlation radiometer, in a particular embodiment. Also, one embodiment of the SWIR light source may be an all-fiber integrated SWIR SC source, which leverages the mature technologies from the telecommunications and fiber optics industry. Beyond natural gas, active remote sensing in the SWIR may also be used to identify other materials such as vegetation, greenhouse gases or environmental pollutants, soils and rocks, plastics, illicit drugs, counterfeit drugs, firearms and explosives, paints, and various building materials.
In one or more embodiments, a smart phone or tablet comprises an array of laser diodes configured to generate light having one or more optical wavelengths, wherein at least a portion of the one or more optical wavelengths is a near-infrared wavelength between 700 nanometers and 2500 nanometers, and wherein at least a portion of the array of laser diodes is configured to be pulsed. One or more lenses is configured to receive a portion of the light from the array of laser diodes and to direct the portion of the light from the array of laser diodes to a sample. A detection system comprises a photodiode array with a plurality of pixels coupled to CMOS transistors, wherein the detection system is configured to receive at least a portion of light reflected from the sample, and wherein the detection system is configured to be synchronized to the light from the at least a portion of the array of laser diodes. The detection system is configured to perform a time-of-flight measurement by measuring a time difference between the generated light from the at least a portion of the array of laser diodes and the at least a portion of light reflected from the sample. The detection system is further configured to: receive light while the array of laser diodes is off and convert the received light into a first signal; and receive light while at least a part of the array of laser diodes is on and convert the received light into a second signal, the received light including at least some of the at least a portion of the light reflected from the sample. The smart phone or tablet is configured to difference the first signal and the second signal and to generate a two-dimensional or three-dimensional image using at least a portion of the time-of-flight measurement, wherein the smart phone or tablet further comprises a wireless receiver, a wireless transmitter, a display, a voice input module, and a speaker.
In one or more embodiments, a smart phone or tablet comprises an array of laser diodes configured to generate light having one or more optical wavelengths, wherein at least a portion of the one or more optical wavelengths is a near-infrared wavelength between 700 nanometers and 2500 nanometers, and wherein at least a portion of the array of laser diodes is configured to be pulsed. One or more lenses configured to receive a portion of the light from the array of laser diodes is configured to direct the portion of the light from the array of laser diodes to a sample. A detection system comprises a photodiode array with a plurality of pixels coupled to CMOS transistors, wherein the detection system is configured to receive at least a portion of light reflected from the sample, and wherein the detection system is configured to be synchronized to the at least a portion of the array of laser diodes. The detection system is further configured to perform a time-of-flight measurement by measuring a time difference between the generated light from the at least a portion of the array of laser diodes and the at least a portion of light reflected from the sample. The smart phone or tablet is configured to generate a two-dimensional or three-dimensional image using at least a portion of the time-of-flight measurement. The smart phone or tablet further comprises a wireless receiver, a wireless transmitter, a display, a voice input module, and a speaker.
Embodiments include a smart phone or tablet comprising an array of laser diodes configured to generate light having one or more optical wavelengths, wherein at least a portion of the one or more optical wavelengths is a near-infrared wavelength between 700 nanometers and 2500 nanometers, and wherein at least a portion of the array of laser diodes is configured to be pulsed at a modulation frequency. One or more lenses configured to receive a portion of the light from the array of laser diodes is configured to direct the portion of the light from the array of laser diodes to a sample. A detection system comprises a photodiode array with a plurality of pixels coupled to CMOS transistors, wherein the detection system is configured to receive at least a portion of light reflected from the sample, is configured to be synchronized to the at least a portion of the array of laser diodes, and is configured to use a lock-in technique that detects the modulation frequency. The detection system is further configured to perform a time-of-flight measurement by measuring a time difference between the generated light from the at least a portion of the array of laser diodes and the at least a portion of light reflected from the sample. The smart phone or tablet is configured to generate a two-dimensional or three-dimensional image using at least a portion of the time-of-flight measurement, wherein the smart phone or tablet further comprises a wireless receiver, a wireless transmitter, a display, a voice input module, and a speaker.
In one or more embodiments, a measurement system includes a light source configured to generate an output optical beam, comprising a plurality of semiconductor sources configured to generate an input optical beam, a multiplexer configured to receive at least a portion of the input optical beam and to form an intermediate optical beam, and one or more fibers configured to receive at least a portion of the intermediate optical beam and to form the output optical beam. At least a portion of the one or more fibers comprises a fused silica fiber. The output optical beam comprises one or more optical wavelengths, at least a portion of which are between 700 nanometers and 2500 nanometers and has a bandwidth of at least 10 nanometers. The system also includes a measurement apparatus configured to receive a received portion of the output optical beam and to deliver a delivered portion of the output optical beam to a sample, wherein the delivered portion of the output optical beam is configured to generate a spectroscopy output beam from the sample. A receiver is configured to receive at least a portion of the spectroscopy output beam having a bandwidth of at least 10 nanometers and to process the at least a portion of the spectroscopy output beam to generate an output signal, wherein the receiver processing includes at least in part using chemometrics or multivariate analysis methods to permit identification of materials within the sample. The light source and the receiver are remote from the sample, and the sample comprises plastics or food industry goods.
In various embodiments, a measurement system includes a light source configured to generate an output optical beam, the light source comprising a plurality of semiconductor sources configured to generate an input optical beam, a multiplexer configured to receive at least a portion of the input optical beam and to form an intermediate optical beam, and one or more fibers configured to receive at least a portion of the intermediate optical beam and to form the output optical beam. At least a portion of the one or more fibers comprises a fused silica fiber. The output optical beam comprises one or more optical wavelengths, at least a portion of which are between 700 nanometers and 2500 nanometers, and has a bandwidth of at least 10 nanometers. The system also includes a measurement apparatus configured to receive a received portion of the output optical beam and to deliver a delivered portion of the output optical beam to a sample, wherein the delivered portion of the output optical beam is configured to generate a spectroscopy output beam from the sample; and a receiver configured to receive at least a portion of the spectroscopy output beam having a bandwidth of at least 10 nanometers and to process the at least a portion of the spectroscopy output beam to generate an output signal, wherein the receiver processing includes at least in part using chemometrics or multivariate analysis methods to permit identification of materials within the sample. The output signal is based at least in part on a chemical composition of the sample. The spectroscopy output beam comprises at least in part spectral features of hydrocarbons or organic compounds.
In at least one embodiment, a measurement system includes a light source configured to generate an output optical beam, comprising a plurality of semiconductor sources configured to generate an input optical beam, a multiplexer configured to receive at least a portion of the input optical beam and to form an intermediate optical beam, and one or more fibers configured to receive at least a portion of the intermediate optical beam and to form the output optical beam. At least a portion of the one or more fibers comprises a fused silica fiber. The output optical beam comprises one or more optical wavelengths, at least a portion of which are between 700 nanometers and 2500 nanometers, and has a bandwidth of at least 10 nanometers. The system includes a measurement apparatus configured to receive a received portion of the output optical beam and to deliver a delivered portion of the output optical beam to a sample, wherein the delivered portion of the output optical beam is configured to generate a spectroscopy output beam from the sample, and a receiver configured to receive at least a portion of the spectroscopy output beam having a bandwidth of at least 10 nanometers and to process the at least a portion of the spectroscopy output beam to generate an output signal. The receiver processing includes at least in part using chemometrics or multivariate analysis methods to permit identification of materials within the sample. The output signal is based on a chemical composition of the sample, which comprises tissue including collagen and lipids.
In one embodiment a remote sensing system is provided with an array of laser diodes, one or more scanners, and a detection system. The array of laser diodes is adapted to generate light having an initial light intensity and one or more optical wavelengths, wherein at least a portion of the one or more optical wavelengths is a near-infrared wavelength between 700 nanometers and 2500 nanometers, and wherein at least a portion of the array of laser diodes comprises one or more Bragg reflectors. The one or more scanners comprises moving mirrors that configured to receive a portion of the light from the array of laser diodes and to direct the portion of the light from the array of laser diodes to an object. The moving mirrors are configured to scan the received portion of the light across at least a part of the object. The detection system comprises a photodiode array with a plurality of pixels coupled to CMOS transistors, wherein at least a portion of the photodiode array comprises an indium gallium arsenide semiconductor. The detection system is configured to receive at least a portion of light reflected from the object, wherein the detection system is configured to be synchronized to the at least a portion of the array of laser diodes comprising Bragg reflectors. The detection system is further configured to perform a time-of-flight measurement, and wherein the detection system further comprises one or more filters to select at least some of the one or more optical wavelengths. The remote sensing system is configured to generate a two-dimensional or three-dimensional mapping using at least a portion of the time-of-flight measurement. The remote sensing system is configured to improve signal-to-noise ratio of at least a portion of the two-dimensional or three-dimensional mapping by increasing light intensity of the array of laser diodes relative to the initial light intensity. The at least a portion of the one or more optical wavelengths falls within an eye safe window corresponding to an optical wavelength longer than 1400 nanometers. The remote sensing system is adapted to be mounted on a vehicle, wherein the at least a portion of the two-dimensional or three-dimensional mapping is combined with global positioning system information, and wherein the remote sensing system is configured to communicate with a cloud.
In another embodiment, a remote sensing system is provided with one or more laser diodes, one or more scanners, and a detection system. The one or more laser diodes are configured to generate light having an initial light intensity and one or more optical wavelengths, wherein at least a portion of the one or more optical wavelengths is a near-infrared wavelength between 700 nanometers and 2500 nanometers. The one or more scanners are configured to receive a portion of the light from the one or more laser diodes and to direct the portion of the light from the one or more laser diodes to an object, wherein the one or more scanners are configured to scan the received portion of the light across at least a part of the object. The detection system comprises a photodiode array comprising semiconductor material. The detection system is configured to receive at least a portion of light reflected from the object, wherein the detection system is configured to be synchronized to at least a portion of the one or more laser diodes. The detection system is further configured to perform a time-of-flight measurement, and wherein the detection system further comprises one or more filters to select at least some of the one or more optical wavelengths. The remote sensing system is configured to generate a two-dimensional or three-dimensional mapping using at least a portion of the time-of-flight measurement. The remote sensing system is configured to improve signal-to-noise ratio of at least a portion of the two-dimensional or three-dimensional mapping by increasing light intensity of the one or more laser diodes relative to the initial light intensity. The remote sensing system is configured to use artificial intelligence to process the at least a portion of the time-of-flight measurement, wherein the artificial intelligence comprises pattern identification or classification. The remote sensing system is configured to apply regression signal processing methodologies to the at least a portion of the time-of-flight measurement.
In yet another embodiment a remote sensing system is provided with one or more laser diodes, one or more scanners, and a detection system. The one or more laser diodes are configured to generate light having an initial light intensity and one or more optical wavelengths, wherein at least a portion of the one or more optical wavelengths is a near-infrared wavelength between 700 nanometers and 2500 nanometers. The one or more scanners are configured to receive a portion of the light from the one or more laser diodes and to direct the portion of the light from the one or more laser diodes to an object, wherein the one or more scanners are configured to scan the received portion of the light across at least a part of the object. The detection system comprises a photodiode array comprising semiconductor material, wherein at least a portion of the photodiode array is coupled to an amplifier having a gain configured to improve detection sensitivity. The detection system is configured to receive at least a portion of light reflected from the object, wherein the detection system is configured to be synchronized to at least a portion of the one or more laser diodes. The detection system is further configured to perform a time-of-flight measurement, and wherein the detection system further comprises one or more filters to select at least some of the one or more optical wavelengths. The remote sensing system is configured to generate a two-dimensional or three-dimensional mapping using at least a portion of the time-of-flight measurement. The remote sensing system is configured to improve signal-to-noise ratio of at least a portion of the two-dimensional or three-dimensional mapping by increasing light intensity of the one or more laser diodes relative to the initial light intensity. The remote sensing system is configured to use artificial intelligence to process the at least a portion of the time-of-flight measurement. The remote sensing system is at least in part configured to identify the object, and a property of the at least a portion of the time-of-flight measurement is compared by the remote sensing system to a threshold.